From DE 42 44 484 there has become known a rotary damper with which in a damping chamber which contains a viscous medium there is arranged a vane which is mounted upon shaft. With a rotation of the shaft the medium is displaced and flows between the end of the vane and the chamber wall. With the known rotary damper the vane is inclined towards one side in the circumferential direction and is deformable or bendable relative to the shaft in a manner such that it is pivoted towards the cylindrical chamber wall when the shaft undergoes rotation in the inclination direction is pivoted towards the shaft when shaft undergoes rotation in the opposite direction. By means of this structure a rotary damper is provided which in opposite rotational directions creates a damping effect of differing strength. With a pivoting of the vane in the direction of the chamber wall, the gap defined with respect to the wall is reduced so that a relatively high braking force is developed. If the shaft however is rotated in the opposite direction, the vane pivots in the direction of the shaft so that the distance of the vane to the cylindrical chamber wall is enlarged. By means of this structure a larger flow cross section is provided, and the rotational force in this direction is braked much less. As a result with such a rotary damper a type of free-running is created.
There are cases in which the braked movement of an actuated part is often not sufficient to prevent damage, for example with back rests or the like.